>> welcome to the "journal" from dw in berlin. >> coming up -- syrian rebels faceau.s. probefor alleged war crimes after a video appears to show mass executions of prisoners. >> president barack obama and republican challenger mitt romney go back on the attack in the final stages of the election battle. >> and seeking clarity -- german chancellor angel merkel on how to develop renewable energy. we begin in syria where the military is currently stepping up its use of airpower in an effort to defeat the rebels. >> opposition forces say at least 70 people have been killed in an air strike near the turkish border. meanwhile, a video emerges of what appears to be opposition fighters executing government soldiers. >> the un says that if the video is authenticated, the action would constitute a war crime. >> as their prisoners cower in terror, rebels celebrate. this video is said to of been recorded in northwestern syria. government forces and rebels have been fighting there for weeks. on thursday, rebels stormed several army checkpoints. they appear to have captured these governme